Survival of the fittest is the absolute law of the Beastkin world, a place where the weak are oppressed and the strong run rampant. In this brutal land, the great king who once unified the entire world returns after a long slumber. His name is Ouma, the legendary Beast King who brought peace to all tribes thousands of years ago before vanishing into history.

The setting is a dark fantasy dystopia populated by various beastfolk, from lion and tiger clans who rule as the dominant predatory species to rabbit and mouse tribes who are exploited, enslaved, or even consumed as food. When Ouma awakens from his millennia-long sleep in an ancient ruin, he finds his once-orderly kingdom has degenerated into chaos. Enraged that unworthy brutes have defiled his garden and that his beloved people are suffering, he declares his intention to reconquer the world and restore it to its proper state.

Ouma possesses an overwhelming power called the King Soul that sets him above all other beasts. His first follower is Inami, a rabbit beastkin girl he meets by chance. Unlike typical heroes who fight for justice or revenge, Ouma acts out of royal pride and ownership over the world itself, unable to tolerate that his property has become ugly and disorderly. His methods rely not on negotiation or diplomacy but on absolute force to make the current rulers understand their place.

Throughout his journey, Ouma defeats the bosses who control various territories. However, he gradually uncovers a deeper threat behind the world's decay, a hidden conspiracy orchestrated by the human race called the Yumano, who seek to exterminate the beastfolk and use the planet for their own prosperity. This leads to a climactic confrontation where Ouma is temporarily sealed away by the humans, forcing his companions to rally across species boundaries to free him for a final battle determining the survival of all beastkind.

The manga is created by Hiroumi Aoi, known for the horror series Shibuya Goldfish, and it reinvents that creator's signature approach to depicting helpless prey and overwhelming violence from the perspective of the ultimate predator. The series is relatively compact, spanning four volumes, and tells a complete story centered on the kings determination to make the world beautiful again on his own terms. Rise up, unite, and long live the king.